The present embodiments relate to ultrasound imaging. In particular, ultrasound shear wave imaging may be improved.
Shear wave velocity information may be useful for diagnosis. Shear wave information may indicate tissue characteristics in addition to acoustic impedance (e.g., B-mode) and Doppler (e.g., flow mode) imaging. However, the complexity of shear wave propagation in tissue may result in significant errors. For example, shear wave velocity may be less accurately determined for fluid or fluid tissue, resulting in seemingly arbitrary values.
To remove the effects of fluid from shear wave images, fluid regions may be separated from solid tissue regions by measuring the flow after stirring. For stirring, acoustic energy is used to generate streaming in fluid. A correlation coefficient between successive or sequential echo signals is computed to distinguish solid tissue from the stirred fluid. However, in live scanning, the motion of solid tissue may produce the same magnitude of decorrelation as fluid motion induced by the acoustic energy stirring. The ability to distinguish may be limited.